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New drive letter E: pointing to TEMP?

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18 replies

by daring

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A new drive popped up on my Windows XP box at work, which shows up as E: Drive, has the same name and properties of my C: drive, and when I view the contents, it shows the files in my TEMP folder. Whazaa? It's not causing a problem at this time, but I know how things like this can snowball. Disk Management does not show the drive at all.

A related issue happened last week when I plugged in my thumb drive which was assigned E:, and it showed the contents of my TEMP folder.

Any ideas on why this is happening?

18 replies

by Former member

And then see if it shows in your Disk Management. If it does not show in there have a look at Drive "E", and see what that says. If it shows up as "E" then right click on it and give it a another letter like "D". Reboot and see if the drive in question is showing as ok. You will have to format the drive as well.

Please post back if you have any more problems or questions.

by daring

There is a misunderstanding - I did not install a new hard drive in the PC. This mystery E: drive just popped up out of nowhere today, and I'm trying to figure out why it's there.

by Former member

have a look at the "E" drive in the device management, if it has showed up out of no where then it will show in the device management section also. If still no joy, download this:
Ccleaner:
http://www.ccleaner.com/
This will clear out your TEMP files and should rectify the issue.

Please post back if you have any more problems or questions.

by thumbsup2

If this is a computer at work, the first thing you should do is check with your system administrator, network administrator, "The IT Guy/Gal", or who ever is in charge of your network. It's entirely possible they've pushed something out to your machine at the mininum, possibly others, which you shouldn't be messing with.

If you don't have a Sys Admin at work, just right click the drive and choose "Disconnect". Then... run a full system scan for viruses and spyware. If you didn't put the drive there and you don't have a Sys Admin to put it there, somebody/something else has done it.

...

by daring

I am the network admin here :)

I'm very familiar with Windows XP and know almost everything about using it, customizing it, and optimizing it. I also have my MCSE. I can guarantee that there is no spyware or virus on this PC, because I know it inside and out, and thoroughly clean it weekly. This is why I'm posting - since I can usually solve every problem, but have never encountered this issue before.

I already tried to see if it shows up in my Mapped Drives list, but it's not there. Somehow Windows thinks it's a physical drive. What a mystery!

by Former member

WARNING!!!!
Any changes you make in the registry could make the computer unstable or UN-operable.

Delete Usb Drive Letter via Registry to Remove Conflict .

In Windows operating system especially Windows XP, when plug in external USB or FireWire mass storage device such as USB key, flash drive, portable harddrive, the drive is not been assigned a drive letter by the system, hence the USB drive or FireWire drive is not showing in Explorer and no AutoPlay or AutoRun window pops up, although the device has been detected, in Safely Remove Hardware (show device but with no drive letter) wizard. The cause is probably due to ?stupid? behavior of XP where it won?t find an available letter from the free letters pool when the USB or FireWire external drive which has previously mounted and assigned a drive letter is been inserted to computer USB or FireWire port again, but that previously allocated drive letter has been taken up and used by another storage devices. Another possible reason is all 26 letters in alphabet has been used, but this situation is rare and unlikely.

There is a solution to USB or FireWire drive not showing in system error. However, the disconnect conflicted storage device to free up the drive letter fix may not be practicable or usable by some, such as computers which are on a network or system running data transfer activity to all its drive assignments continuously flow without stopping, and thus disconnect or reassigning any mapped drives, networked drives, removable drives or other storage drives is not an option.
In this situation, there is another workaround hack to fix the no USB or FireWire drive issue. The workaround fix relies on the registry tweak below to change the drive letter that has been previously assigned to the mounted USB or FireWire portable mobile flash or hard disk drive. Or if users wish, can opt to delete any reference to the detected drives by the device so that when the storage device is plugged in again, the whole drive letter assignment will be start from fresh, and clean.
1.Login to Windows as an Administrator.
2.Open Registry Editor by typing regedit (or regedt32.exe in older Windows prior to XP) in Run command of Start Menu and then press Enter.
3.Navigate to the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices
4.Optional step which not required in Windows XP or later, right click on MountedDevices, then select Permissions. You can also click Permissions from the Security menu.
5.Optional step which not required in Windows XP or later, check the option to make sure that Administrators have full control to the registry key. Change and revert back this setting when you are finished with the reset of the steps.

6.If you run above 2 steps in OS earlier than Windows XP, quit regedt32.exe and run regedit.exe.
7.Also in the HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices registry branch selected, in the right pane, find and locate a registry value which represents the troubled USB or FireWire drive. The registry key should have the name that resembles the format of \DosDevice\X: where X can be any alphabet letter which corresponding to your physical system drive letter.

Here?s a guidelines that you can follow to quickly determine which registry key is linked to your conflicted drive letter:
Exclude \DosDevice\A: and \DosDevice\B: which normally reserved for floppy disk drives.
Exclude \DosDevice\C: which normally is the system root drive.
If you have more than one fixed hard disk drives, then any drive letters that are using by them is not possible linked again, UNLESS the additional hard disk drive is added AFTER you first use the USB or FireWire device that now unable to show.
Same case with CD-ROM or DVD-ROM optical drive as above reasoning.
If you have inserted and mounted a lot of thumbdrives, USB flask drive, or external hard disks before, you will likely still see a lot of remaining registry values that you won?t know which is which. In this case, double click on each remaining registry key values to view its binary data. Inside the binary data, there will be trace of the name of the device that this registry key represents.

Please post back if you have any more problems or questions.

by daring

Device Manager is all correct because, again, there is no new hardware installed. The mystery E: drive pops up with the same properties as my C: drive. Even the drive label "WinXP" that I gave my C: drive, shows up on the E: drive.

Cleaning my temp files has no effect on the situation. Whatever is causing this issue is probably defaulting to the temp directory when it tries to browse a non-existent drive.

by daring

Thanks, Peconet. I think this will help narrow down the situation. But since I don't have any USB keys plugged in right now, I can't try what the article suggests. My mystery E: drive still exists.

Unfortunately, the registry key for my mystery E: drive does not lead to anything helpful. The key contains seemingly random characters. The key corresponds with a volume listed in the same key as:
\??\Volume{d464c5ed-ccd1-11db-bca8-0019b91c736b}
... but I don't know if this is helpful.

I do have many other DosDevices pointing to various SD cards and external drives that had been plugged in previously.

by Former member

Backup your registry before you do anything, and then delete the key the you have posted. i am pretty sure you know how to back up your registry. When done delete the key in question and reboot your computer. This should rectify the issue.

Please post back if you have any more problems or questions.

by daring

Oh, I absolutely would have already deleted the key except for the similarity to the properties of my C: drive. I don't want to delete the key and then not be able to boot up ever again. Maybe I will take a ghost image first and try this, but for right now it's not causing enough of a problem.

by bizzo

Do the properties of the drive have it as a local or a network drive?

Is your C:\temp folder shared?
It might be that the folder is shared, and the share has been mapped to your E drive. That is why it doesn't show up in disk management and why your USB drive tries to use the same drive letter.

Disconnect the drive through explorer, and remove the share on C:\Temp.

by daring

It is showing as a local drive. The drive properties of E: are the same as C:. This includes drive label, free space, disk type, etc. However, the Disk Cleanup button is hidden, and attempting a Defrag gives an error that this drive type is not supported.

C:\Temp\ is not shared, nor is the temp folder in my user profile, which is what E: is pointing to.

by churdoo

I can't explain HOW it happened, but this sounds like something ran or effectively applied the following command on your workstation:
SUBST E: c:\temp

And I don't think that SUBST is persistent, so that indicates that something may be running it each time you start or log onto your computer.

The opposite of SUBST is /d, so from a CMD prompt:
SUBST E: /d
should delete the E: drive.

Another spot to look is here:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\DOS Devices]
"E:"="C:\\temp"

If the above key is present, delete it and reboot and E: will be gone.

by daring

AWESOME! I think that may have fixed it. Thanks Churdoo!

I don't know when or why that command would have ever been run, or any process similar to it. I'll check to see if the drive still exists after a reboot.

by churdoo

After reboot, if E: comes back, then look at that registry key I posted.

by daring

It did happen again today, but that registry entry did not exist. The SUBST trick worked again however, so thanks again!

by kenone

Type;
net use
does it show up?
Try deleting it;
net use [DEVICE [/HOME[{PASSWORD | *}] [/DELETE:{yes | no}]]

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